Abstract The external pollen morphology of Helianthemum caput-felis Boiss. (Cistaceae) was studied from nine populations covering the whole distribution range in the western Mediterranean Basin, using light and scanning electron microscopy. Pollen grains are medium sized, radially symmetrical and tricolporate, and the pollen shape varies from sub-prolate to prolate-spheroidal. According to the exine ornamentation, three main pollen subtypes were recognised: striato-microperforate, microreticulate and rugulato-microperforate. The pollen data demonstrate that the populations of North Africa, as well as one population of the Spanish island of Majorca (Sa Ràpita), show similar micro-reticulate exine ornamentation. The other Spanish populations of Alicante, Colònia de Sant Jordi (Majorca), as well as those of the Italian area of Capo Mannu (Sardinia), show a striato-microperforate pollen type, while the population of Su Tingiosu (Sardinia) shows a rugulato-microperforate pollen type. The different characteristics of the exine ornamentation make it a valuable parameter to distinguish the different populations in the distribution range. Our results suggest an evolutive differentiation by the geographical isolation of the species within the Mediterranean Basin.

中文翻译：

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Helianthemum caput-felis Boiss 的花粉形态。（蔷薇科）

摘要 向日葵的外部花粉形态。(Cistaceae) 使用光学和扫描电子显微镜从覆盖地中海西部盆地整个分布范围的 9 个种群中进行研究。花粉粒中等大小，呈放射状对称，呈三孔状，花粉形状从近扁圆形到扁扁球形不等。根据外壁纹饰，识别出三种主要的花粉亚型：纹状微穿孔、微网状和皱状微穿孔。花粉数据表明，北非的种群以及西班牙马略卡岛 (Sa Ràpita) 的一个种群显示出类似的微网状外壁纹饰。阿利坎特，Colònia de Sant Jordi（马约卡岛）的其他西班牙人，以及意大利卡波曼努（撒丁岛）地区的人，显示纹状微穿孔花粉类型，而苏廷吉欧苏（撒丁岛）的种群显示出皱状微穿孔花粉类型。外壁纹饰的不同特征使其成为区分分布范围内不同种群的重要参数。我们的结果表明地中海盆地内物种的地理隔离导致了进化分化。